Expanded mesh

ABSTRACT

A method of forming expanded mesh which comprises forming an extrusion having a constant cross-sectional shape which includes webs separated by ribs, forming rows in its slots in the webs which overlap one another and are staggered, increasing the width of each slot of the two outermost rows of slots by bending the ribs, engaging the widened slots over the hooks of two rows of hooks of an expanding machine, separating the rows of hooks from one another so as to bend the ribs and expand the slotted extrusion without applying any torsion to the ribs, and at the same time move the hooks in each row towards one another, and then removing the expanded mesh from the hooks.

Jury et al.

[ Dec. 3, 1974 EXPANDED MESH [75] Inventors: l-larold Rex Jury, Norwood; Ronald McKenzie Howells, Yennora, New South Wales, both of Australia I [73] Assignee: Comalco (J. & S.) Pty. Limited,

New South Wales, Australia [22] Filed: Aug. 20, 1973 [21] Appl. No.: 389,954

[30] Foreign Application Priority Data Aug. 23, 1972 Australia 0185/72 [52] US. Cl. 29/6.l [51] llnt. Cl B2ld 31/04 [58] Field of Search 29/61 [56] References Cited UNITED STATES PATENTS 885,158 4/1908 Kahn .L 29/6.l 1,103,033 7/1914 Clark 29/6.l

' A method of forming expanded mesh which comprises Herr 29/6.l Ullman 29/6.l

Primary Examiner-Andrew R. .luhasz Assistant Examiner-Leon Gilden Attorney, Agent, or Firm-Jay L. Chaskin, Esq.

ABSTRACT forming an extrusion having a constant cross-sectional shape which includes webs separated by ribs, forming rows in its slots in the webs which overlap one another and are staggered, increasing the width of each slot of the two outermost rows of slots by bending the ribs, engaging the widened slots over the hooks of two rows of books of an expanding machine, separating the rows of hooks from one another so as-to bend the ribs and expand the slotted extrusion without applying any torsion to the ribs, and at the same time move the hooks in each row towards one another, and then removing the expanded mesh from the hooks.

6 Claims, 16 Drawing Figures PATENIEL DEE 31974 SHEET 1 BF 6 PATENTED DEC 3 74 SHEET 5 [IF 6 PATENTEL, DEC 3 I974 3 ,851,362 sum 80F e v @wgm EXPANDED MESH BACKGROUND OF THE INVENTION The US. Pat. No. 2,018,085 dated Oct. 26th, 1935 and issued to O. M. Otte described a method of making a flat expanded grill wherein-a sheet of material was first formed into corrugations extending in the direction in which the material was to be expanded, slitting the material at spaced positions with the slits extending at right angles to the corrugations, and then expanding or pulling out the slit portions of the material and at the same time flattening the corrugated parts into the plane of the originalstrip or sheet. By utilising corrugated portions extending across the bars or strips, the extra length required in the expansion of the material was provided'by the flattening of the corrugations. With this arrangement the length of the expanded product was substantially the same as thelength of the unexpanded product.

Another specification which refers to the formation of an expanded metal without applying torsion to the expanding bars was the specification No. 21,801 issued in Great Britain and dated the th Sept., l9l0, having been issued to Tentschert, and in that specification there was described a method of forming a lattice work for a window frameor for other purposes by drawing out laterally a metal plate provided with longitudinal ribs and intermediate slits, strips being left between each pair of longitudinal ribs on each'of the slits, so as to form flanges lying in the plane of the plate when the latter is drawn out. The unperforated portions of the rib plate was provided with cross-ribs, and thevplate was suitable for production for example'by casting or coining metal. The unperforated metal was not of constant cross-section throughout its length.

MAIN-OBJECTS OF THE INVENTION The main object of the invention is to provide a methodof forming an expanded mesh which will be much more suited to production techniques than either' of the above proposals and therefore results in a low cost expanded mesh. A second object is to provide a method whereby expanded meshes of different configurations can be quickly and easily formed in expanding means with a minimum of set up time. A still further object of the invention is to provide a method which is particularly suitable for non-corrosive metals.

BRIEF SUMMARY OF THE INVENTION moving the hooks in each row towards one another,

and removing the expanded mesh from the hooks.

In our co-pending Australian application No. RE. 197 there is described a means and method for expanding a workpiece wherein the hooks of an expanding machine are carried on carriage blocks, the blocks moving towards one another when the bending takes place. This provides a simple and effective means for the limiting of inward movement toward one another of the carriage blocks which in turn assists in maintaining an even pattern in the expanded me'tal. Furthermore, the opening of the two outermost rows of slots facilitate positioning the workpiece on the hooks.

More specifically a method of forming expanded mesh in this invention comprises:

(a) extruding extrusile metal to form an extrusion having a constant cross-sectional shape which includes ribs separated by webs,

- (b) forming a row of slots in each web so that the slots of each row are staggered with respect to and overlap the slots of at least one adjacent row,

(c) increasing the width of each slot in each of the two outermost rows of slots by bending at least one of the ribs flanking the respective slot,

(d) engaging the hooks of two rows of hooks of an expanding machine in respective widened slots of respective said outermost rows of slots,

(e) separating the rows of hooks from one another so as to bend the ribs and expand the slotted extrusion, and at the same time move the hooks in each row towards one another, and

(f) removing the expanded mesh from the hooks.

One great advantage of this invention is that it enables the widening of the outermost rows of slots to take place without any separate operation requiring handling of a workpiece, and further in this invention a slotting machine having aseries of slotting rollers on a slotting roller shaft is also provided with a spreader finger shaft having at least one pair of spreader fingers which are radially outstanding therefrom and which are aligned with the respective outermost 'slotting rollers, the spreader finger shaft being driven along with the slotting roller shaft and arranged so that the spreader fingers are driven into the slots of the respective outermost rows of slots to thereby effect the increasing of slot width as the workpiece passes through the slotting machine. A slotting machine which can be readily modified for use with this invention is described in our copending Australian Pat. application No. 57895/73.

More specifically, further according to this invention the slots are formed by a series of axially spaced slotting rollers carried on a slotting roller shaft which'is journalled in bearings in the frame of the slotting machine, the machine-also having a spreader finger shaft which is journalled in bearings in said frame and parallel to the slotting roller shaft and has a pair of radially outstanding spreader fingers thereon which are aligned with respective outermost slotting rollers, the method further comprising simultaneously:

(a) driving the extrusion in a longitudinal direction past the slotting rollers,

(b) rotationally driving the slotting roller shaft, and

I (c) rotationally driving the spreader finger shaft to drive the spreader fingers into the slots of the respec- BRIEF DESCRIPTION OF TI-IE DRAWINGS An embodiment of the invention is described hereunder in some detail with reference to and is illustrated in the accompanying drawings in which:

FIG. 1 is a cross-section of an extrusion having a constant cross-sectional shape,

FIG. 2 is a plan of the extrusion illustrated in FIG. 1,

FIG. 3 is a cross-section of the extrusion after having been slotted but before the outermost rows of slots are widened,

FIG. 4 is a plan of the slotted extrusion illustrated in FIG. 3,

FIG. 5 is a plan similar to FIG. 4 but illustrating the shapes of the outermost rows of slots after they have been widened,

FIG. 6 is a diagrammatic representation of a slotting machine which is provided with means for widening the outermost rows of slots,

FIG. 7 is a perspective view which illustrates the configuration of the slotting roller,

FIG. 8 is a section through a slotting machine which is provided with spreading fingers,

FIG. 9 is an enlarged elevational view of a spreading finger carrier with spreading fingers thereon,

FIG. 10 is a section taken on line 10-10 of FIG. 9,

FIG. I] is a section taken on line ll-ll of FIG. 9,

FIG. 12 is a fragmentary view of portion of an expanding machine showing means utilised to correctly locate the hooks of a row of hooks relative to one another,

FIG. 13 is a diagrammatic plan illustrating the workpiece of FIG. 5 when engaged on the hooks of a metal expanding machine, but before expansion of the workpiece,

FIG. 14 is a fragmentary diagrammatic plan illustrating the configuration of the workpiece after expansion and the arrangement of the hooks,

FIG. 15 is a plan of portion of one expansion rail of an expanding machine and the position of the hook carriage as relative to one another after expansion has taken place, and

FIG. 16 is a section taken on line 16-l6 of FIG. 15 but drawn to an enlarged scale.

Referring first to FIGS. 1 to 5, FIG. 1 illustrates an extrusion 20 of ductile and extrusile metal, in this embodiment being of aluminium alloy, and being provided with a plurality of ribs 21 which are separated by webs 22. In FIGS. 3, 4 and 5, the workpiece is shown as slotted with a series of slots designated 24, each web 22 containing a row of slots, and in this embodiment each row has its slots overlapping the slots of the or each adjacent row as the case may be, and being staggered with respect thereto. As shown in FIGS. 4 and 5, the slots of each row of slots have their adjacent ends close to one another being separated by only a short length ofweb 22 in each instance. In FIG. 5 it willbe seen that the outermost rows of slots 24 have been widened by bending of the outermost rib 21 in each case.

FIG. 6 illustrates diagrammatically a slotting machine, and FIG. 8 is a section through the slotting head thereof. FIG. 7 illustrates the slotted roller arrangement. In FIG. 6 it will be seen that a driving chain 27 is provided with a plurality of outstanding dogs 28 which are arranged to drive a workpiece extrusion 20 in a longitudinal direction past a series of slotting rollers 29. As shown more particularly in FIG. 7, each slotting roller 29 is provided with a pair of diametrically opposite recesses 30 having between them radially outstanding and circumferentially extending projections 31 which, as shown in FIG. 8, effect the formation of slots in the workpiece. The slotting rollers 29 are separated from one another by circular packers 33 (FIG. 7), and are joined thereto by bolts 34 extending through bolt holes 35. The rollers are keyed to a slotting roller shaft 36 (FIG. 8). The circular packers 33 are contained within retaining plates 38 which are illustrated only in FIG. 7, but which are effective in preventing the workpiece 20 from distorting as the slotting takes place. As illustrated in FIG. 8, a spreader head 40 is secured to the frame of the slotting machine, being spaced on the outside of the slotted rollers 29. The spreader head 40 carries on it a pair of bearings (not shown) but which are adjustable by means of a screw jack 41 to adjust the height of the bearings, and the bearings journal a spreader finger shaft 42. In a similar way, the height adjustment of the slotting roller shaft 36 is effected by a second screw jack 43 in the slotting roller head 44. Thus the relative heights of the shafts 36 and 42 can be adjusted, enabling the required adjustment to take place in the event that the ribs 21 are higher or lower in one workpiece than in another. A driving chain 46 extends between the shafts 36 and 42 so that the slotting roller shaft 36 and the spreader finger shaft 42 rotate at identical speeds. Provision is made however for the varying of the distances between the shafts, so that the spreader head can be adjusted to have its spreader fingers 47 exactly synchronized with the slotting rollers so as to enter the slots formed in a workpiece.

FIGS. 9, l0 and 11 illustrate the features of a spreader head having two diametrically opposite spreader fingers 47. The number of spreader fingers should be identical with the number of radially outstanding projections 31 when the shafts 36 and 42 are driven at the same speed. However, the number may be varied, and in order to accommodate variation of numbers, the spreader fingers 47 are secured with bolts 50 the heads of which engage in an annular T slot 51 which extends around a face of a spreader finger carrier 52 which is keyed to the spreader finger shaft 42 as shown in FIG. 8. However the spreader finger carrier 52 is slidable on the shaft 42, but is provided with screw threaded members 53 enabling it to be secured in any position which is required for the spreader fingers 47 to be aligned with the respective outermost row of slots 24 in the workpiece.

Since there are two outermost rows of slots, there are two spreader heads opposite one another, and the spreader fingers 47 are axially aligned with one another when the slots of the outermost rows are in line with one another, this being the most usual configuration. As shown in FIG. 10, each spreader finger is of general rectangular shape but is provided with sloping surfaces 55 which enable the finger to enter the slots 24 of the respective outermost rows.

After the workpiece has been slotted and after the outermost rows of slots have been widened, the workpiece is driven by the dogs 28 of the chain 27 onto the discharge side support roll case 56.

FIGS. 12, 13', l4, l and 16 illustrate some details of a metal expanding machine which is described in greater detail in our co-pending AustralianPat. application No. P.B. 197. The machine is provided with side rails 60 which are movable apartfrom one another by means best illustrated in ourco-pending application, each side rail 60 carrying on it a track 61 which is engaged by rollers 62 on carriage blocks 63. Each carriage block 63 has secured to it a workpiece engaging hook 65 which is best illustrated in FIG. 16, and the carriage blocks are interconnected by a flexible line66 which, when taut, approximately positions the hooks which engage over the hooks as the member 67 is swung downwardly and accurately locate the hooks. When the hooks have been so located, the workpiece is placed on them, whereupon the swinging gauge member 67 is removed. The detailed construction of this mechanism is described in the said Australian application P.B. 197.

After the gauge member has been swung out of the way, the side rails 60 are moved away from one another (if desired one of the two may be fixed) and the workpiece is expanded by bending of the metal strips between adjacentslots, as illustrated in FIGS. 14 and 15. In this expansion, a minimum of stretching takes place and the carriage blocks 63 move toward one another until they finally abut one another. This ensures that the module remains unaltered for the whole of the length of the workpiece, andif desired a slight degree of stretching can be imparted to remove any irregularities after the carriage blocks 63 have abutted one another.

This invention results in anew product, namely a mesh wherein the ribs have substantially identical cross-section for the whole of their lengths, wherein there has been little or no strain imparted into the ribs,

and wherein there are no cross ribs at the junctions of the ribs. The invention then makes possible products of a wide range of shape which can be aesthetically pleasing, since the cross-sectional shape of the ribs themselves can be varied.

The method makes it possible to form a workpiece with only three operator handling stations, one at the extrusion stage (FIG. 1) one at the slotting and widening stage (FIG. 5) and one at the final expansion stage (FIG. 14). It will therefore be seen that the product can be of very low cost, and that the method is inherently so versatile that the low cost can be maintained even when production runs are short.

We claim:

1. A method of forming expanded mesh, comprising;

a. extruding extrusile material to form an extrusion having a constant cross-sectional shape which includes ribs separated by webs,

b. forming a row of slots in each web so that the slots of each row are staggered with respect to and overlap the slots of at least one adjacent row,

0. increasing the width of each slot in each of the two outermost rows of slots bybending at least one of a the ribs flanking the respective slot,

d. engaging the hooks of two rows of hooks of an expanding machine in respective widened slots of respective said outermost rows of slots,

e. separating the rows of books from one another so as to bend the ribs and expand the slotted extrusion, and at the same time move the hooks in each row towards one another, and

f. removing the expanded mesh from the hooks.

2. A method according to claim 1 wherein said slots are formed by a series of axially spaced slotting rollers carried on and keyed to a slotting roller shaft which is journalled in bearings in the frame of a slotting machine, said machine also having a spreader finger shaft journalled in bearings in said frame and being parallel to the slotting roller shaft, and having a pair of radially outstanding spreader fingers thereon, the method fur ther comprising simultaneously:

a. driving said extrusion in a longitudinal direction past the slotting rollers,

b. rotationally driving the slotting roller shaft, and

c. rotationally driving the spreader finger shaft to drive the spreader fingers into the slots of the respective outermost rows of slots and thereby effect said increasing of slot width.

3. A method according to claim 2 further comprising adjusting the spreader fingers on the spreader finger shaft to align them with the respective outermost of said slotting rollers on the slotting roller shaft.

4. A method according to claim 2 wherein said expanding machine comprises a pair of side rails each having a trackextending along it, and the books of each said row are each carried on a carriage block having rollers thereon which engage and are supported by a said track, the carriage blocks of each row being interconnected by'a flexible line, the method further comprising drawing the lines taut to thereby separate the carriage blocks from one another before engaging the hooks in said respective widened slots.

5. A method according to claim 2 wherein said expanding machine comprises a pair of side rails, each side rail having a swinging gauge member hinged thereto, the gauge member having cut-outs therein, a track extending along each side rail, a plurality of carriage blocks each having rollers thereon which engage and are supported by a said track, each said hook being on a respective carriage block, the carriage blocks of each row being interconnected by a flexible line, the method further comprising:

drawing said lines taut to thereby separate the carriage blocks from one another, swinging the gauge member over the carriage blocks so as to position the cut-outs over the hooks when the lines are taut to thereby accurately locate the hooks in a spaced relationship, and retaining the hooks in that spaced relationship while engaging the hooks in respective widened slots.

6. A method according to claim 5 wherein separating of the rows of hooks away from one another is continued at least until said carriage blocks abut one another. =0: 

1. A method of forming expanded mesh, comprising: a. extruding extrusile material to form an extrusion having a constant cross-sectional shape which includes ribs separated by webs, b. forming a row of slots in each web so that the slots of each row are staggered with respect to and overlap the slots of at least one adjacent row, c. increasing the width of each slot in each of the two outermost rows of slots by bending at least one of the ribs flanking the respective slot, d. engaging the hooks of two rows of hooks of an expanding machine in respective widened slots of respective said outermost rows of slots, e. separating the rows of hooks from one another so as to bend the ribs and expand the slotted extrusion, and at the same time move the hooks in each row towards one another, and f. removing the expanded mesh from the hooks.
 2. A method according to claim 1 wherein said slots are formed by a series of axially spaced slotting rollers carried on and keyed to a slotting roller shaft which is journalled in bearings in the frame of a slotting machine, said machine also having a spreader finger shaft journalled in bearings in said frame and being parallel to the slotting roller shaft, and having a pair of radially outstanding spreader fingers thereon, the method further comprising simultaneously: a. driving said extrusion in a longitudinal direction past the slotting rollers, b. rotationally driving the slotting roller shaft, and c. rotationally driving the spreader finger shaft to drive the spreader fingers into the slots of the respective outermost rows of slots and thereby effect said increasing of slot width.
 3. A method according to claim 2 further comprising adjusting the spreader fingers on the spreader finger shaft to align them with the respective outermost of said slotting rollers on the slotting roller shaft.
 4. A method according to claim 2 wherein said expanding machine comprises a pair of side rails each having a track extending along it, and the hooks of each said row are each carried on a carriage block having rollers thereon which engage and are supported by a said track, the carriage blocks of each row being interconnected by a flexible line, the method further comprising drawing the lines taut to thereby separate the carriage blocks from one another before engaging the hooks in said respective widened slots.
 5. A method according to claim 2 wherein said expanding machine comprises a pair of side rails, each side rail having a swinging gauge member hinged thereto, the gauge member having cut-outs therein, a track extending along each side rail, a plurality of carriage blocks each having rollers thereon which engage and are supported by a said track, each said hook being on a respective carriage block, the carriage blocks of each row being interconnected by a flexible line, the methoD further comprising: drawing said lines taut to thereby separate the carriage blocks from one another, swinging the gauge member over the carriage blocks so as to position the cut-outs over the hooks when the lines are taut to thereby accurately locate the hooks in a spaced relationship, and retaining the hooks in that spaced relationship while engaging the hooks in respective widened slots.
 6. A method according to claim 5 wherein separating of the rows of hooks away from one another is continued at least until said carriage blocks abut one another. 